Chains Of Misery. No, really.

Yes, yes, I know, it's not a well-respected song, but dang it all if I don't find it catchy as all-get-up. But I can't figure out, being tone-deaf as I am. What I do know is that the tab seen here : http://www.ultimate-guitar.com/tabs/i/i ... ry_tab.htm (as well as copied ad nauseum across the net) does not sound right. The main riff (riff A) sounds wrong (particularly the last two chords) and it's missing the fill (or filll as it says it). I can't figure it out. It's also missing the bass, and I'm not sure what's going on with it in the intro, as there's all sorts of wacky 'Arry stuff going on. Can anyone help me out here?